88 lines
2.6 KiB
Python

from __future__ import annotations
from email import message_from_bytes
from typing import TYPE_CHECKING
from django.conf import settings
from django.core.mail import EmailMessage
from filelock import FileLock
if TYPE_CHECKING:
from documents.models import Document
def send_email(
subject: str,
body: str,
to: list[str],
attachments: list[Document],
*,
use_archive: bool,
) -> int:
"""
Send an email with attachments.
Args:
subject: Email subject
body: Email body text
to: List of recipient email addresses
attachments: List of documents to attach (the list may be empty)
use_archive: Whether to attach archive versions when available
Returns:
Number of emails sent
TODO: re-evaluate this pending https://code.djangoproject.com/ticket/35581 / https://github.com/django/django/pull/18966
"""
email = EmailMessage(
subject=subject,
body=body,
to=to,
)
used_filenames: set[str] = set()
# Something could be renaming the file concurrently so it can't be attached
with FileLock(settings.MEDIA_LOCK):
for document in attachments:
attachment_path = (
document.archive_path
if use_archive and document.has_archive_version
else document.source_path
)
friendly_filename = _get_unique_filename(
document,
used_filenames,
archive=use_archive and document.has_archive_version,
)
used_filenames.add(friendly_filename)
with attachment_path.open("rb") as f:
content = f.read()
if document.mime_type == "message/rfc822":
# See https://forum.djangoproject.com/t/using-emailmessage-with-an-attached-email-file-crashes-due-to-non-ascii/37981
content = message_from_bytes(content)
email.attach(
filename=friendly_filename,
content=content,
mimetype=document.mime_type,
)
return email.send()
def _get_unique_filename(doc: Document, used_names: set[str], *, archive: bool) -> str:
"""
Constructs a unique friendly filename for the given document.
The filename might not be unique enough, so a counter is appended if needed.
"""
counter = 0
while True:
filename = doc.get_public_filename(archive=archive, counter=counter)
if filename not in used_names:
return filename
counter += 1